Engineers are investigating after a sinkhole appeared in Thornbury Road, Osterley.
The 6ft wide by 4.5ft deep chasm was cordoned off yesterday (Tuesday, July 29) after being spotted by members of the public.
Hounslow Highways, the council's streets contractor, is now investigating what caused the collapse on the southern carriageway of the road, at the junction with Eversley Crescent.
A council spokesman this morning said traffic diversions had been put in place and access to Eversley Crescent was currently limited.
Hounslow Highways service director Rob Gillespie said: "We thank local residents for alerting us to this incident. Our crews were on site as soon as possible to ensure the safety of motorists and other road users.
"We will continue to investigate the cause of the hole and work with relevant parties to ensure a safe, efficient resolution."
* Have you seen the hole? Are you affected by the diversions? Let us know by emailing email@example.com or tweeting @HounslowChron